I don't think all schools care about individual student achievment. THey focus more on the overall average and how that data can be spun to make they adults look good.

Quote
And despite large educational
expenditures, school spending in the United States
is among the least cost-effective in the world. By one
measure we get 60 percent less for our education dollars in
terms of average test-score results than do other wealthy
nations (Exhibit 3).